Electric plug connecter



Nov. 6, 1928. 1,690,759

W. H. TRIMM ELECTRIC PLUG GoNNEcTER Filed June 24. 1922 Patented Nov. 6, 1928.

UNITED STATES PA'I'ENT OFFICE.

ELECTRIC PLUG CONNECTER.

Application filed June .24,

My invention relates to improvements in A 'rie `lug connecter, and, although capable of many uses, is particularly well fitted for use in connection with portable electric current-responsive devices ot' the two-wire or two-conductor type, for instance telephone receivers or head sets. j

So tar as l 4am aware, prior to my invention, in serially connecting a pair of head sets as'used in radio communication, it had been the custom to use an ordinary twoeconductor plug which two terminals of different head sets were connected, the other two terminals of 'the head sets being coupled or Vconnected together by some sort et a sep- :irate connecter. ln many cases, such separate connecter, or essential parts .of same, such as screws, became lost, in addition to which the loose exposed connecter was unsightly and in other ways troublesome.

The principle object of my invention is to provide in connection with a jack of a twowire supply circuit and a pair of twowire electric currentresponsive devices, a single 'unitary plug insertable in the jack, to which` plug the liour conductors of the devices are connected in such a way as to place the devices in series with each other rather than in multiple. y

Other objects and advantages or' the invention are pointed Vout in the description and in the appended claims.

ln the drawings, which illustrate a specific application of my invention as usedin connection with radio head sets,

Fig. lis a side elevation of the plug, certain parts being shown in section for greater clearness. i

Fig. 2 is an elevation ot the* baclrof the plug, the cover havingl been removed and showing diagrammatically the connections to the head sets.

' Fig.- 3 is an axialsection taken on the line 8-3 of Fig. 2.

` Fig. 4 is a section taken on thev line 4-4 of Fig. 3, and

Fig. 5 is an end elevation of the tip end of the plug.

Referring to the drawings. 10 and 11 represent somewhat diagrammatically the jack springs which are connected to the supply circuit, and which are adapted to make resilient contact respectively with the sleeve 12 and tip 13 ot the plug. As shown best in Fi g. 3, the sleeve 12 is made with a circular flange 14 at its rear end, there also being a 1922 Serialv No. 570,845.

slight enlargement 15 adjacent the flange .w'hich enlargement `pressed into a brass dise 16 'forced up against flange 14. Preferably. the circular seat or enlargement 15 is staked to the disc 16 to lrevent the latter i'roni turniiig on the sleeve l2.'

As shown in Figs. 4 and there are insorted through countersunlr apertures in the brass disc 1G, a of three flat `head screws 17. 1&3 and 19. ihescrews 18 and 19 `fit holes and 21vtapped vinto a relatively thick base of insulating material, such as hard rubber, thereby uniting said parts and disc lil permanently and rigidly to the insulating b se plateor disc 22.` lt will be observed by re Aerence to Figs 3 and 4, that at its center, the side of the insulating discl22 which goes up against the rear lace oit brass disc 16, is recessed in order to admit the circular llange portion 14 of sleeve 12.

@n the baclr of the insulating base 22 there are carried a set ol three terminal or connecter members,` two of which comprise short posts 23 and or square brass rod, while the other yconnecter member comprises two similar posts 25 and 26 united together by a connecter link 27. As shown best in Fig. 2, each ot said posts 23, 24, 25 and 26, is drilled out- .longitudin ally to form an opening as at 28 for receivingthe tip ot rone of the conductors 29, 3l, 31 and 32, the tip in each case being rigidly held in said aperture by means of a set screw as at 33. y

In order to securethe several posts 23, 24, and 26, tothe base 22, the posts at their ends which are adjacent to the'base 22,`

are drilled longitudinally and tapped to receive flat head screws, Als shown in Fig. 1, the flat head screw 1'?, `previously referred to, besides holding in place the terminal post 24, serves also to connect the latter with the sleeve disc 16. The remaining three llat head screws 34, 35, 36, are seated in counterbored recesses as shown at 37 in Fig. 3 and hence serve merely to hold the posts 23, 25

and26 in posit-ion on the rear tace of: base 22 will be observed that link 27,vwhich comprises a thin plate of suitable metallic conduct-ing material, tor instance thin brass or German silver, is interposed. between the posts 25 and 26, and the rear face ol base 22, being' also apertured to admit the screws 35 and 36, so that when said screws 35 and 36 are tightened, a satisfactory connection will be established between linlr 27 and posts 25 and 26.

Similarly, the -tip yconnecter linlr or plate 38 is apertured to admit screw 34 and is interposed between the post 23 and the rear face of base plate 22, so that when screw 34` y is tightened, plate 38 Will'beelectrically cony nected with post 23. The plate 38 is con-v nectedto the tip 13 of the plug, see Fig. 3,

by means of a rod 39, extending` through the sleeve 12 andv insulated thereform by a tube i0 ofhard rubber or other suitable insulating material. rlhe rear end of said rod. 39 is threaded to receive alock nut 41 engaging the `outer face of. connecter plate .3S While By reference to Figf2, it .villbe observed that' the single terminals of the different head sets are connected respectively to the tip and sleeve posts 23 and24, While the other Aterminals and' 31 ofthe head sets are connected to the insulated posts 25 and r26,`Which are themselvesconnected to and by ka plate 27; Hence,

When'the plug 12 is inserted in the jack, the head sets Will be connected-in series Without the necessity of prol viding any external means forconnecting togetlier any of the terminals of the head set cords.' In order to protect and conceal the terminal posts and connections of the plug, I prefer to apply a removable enclosure or cap member 44 large enough to enclose the same, and, in theV present instance,'removably secured on the disc 22 by threading the latter as indicated at 4-5, to lit corresponding threads onk the interior ofthe end of theV cap shaped closure 44s 'f Thedescribed details of construction and arrangement aremerely illustrative of a preferred application of my invention, the scope of which should be Adetermined by reference to the appended claims, said claims being construed asbroadly as` possible, consistent with the state of the art. Y

I claim as my invention: f

1. A telephone type plug for serially feeding a pair of portable tivo-Wire electric current-responsive` devices comprising insulating material, a sleeve provided With a iiange secured to one side' of said disc, three connecting memberscarried by the other side a disc of of said disc, one of said members being connected to'said sleeve, a tip extending'beyond the projecting end of said sleeve and insulated, y therefrom, ya rod, also insulated from said sleeve extending therethrough t tively 'connected tothe tip and sleeve-members.

2. A telephone type plug for serially feed-- ing a pair yof portable two-Wire electric-current-responsive devices comprising a disc of insulatinginaterial, a sleeve provided with a liange secured to one side ofk said disc, three connecting members carried by the other side of said disc, one of said members being connected to said sleeve, a tip extending beyond the projecting end of said sleevey and insulated therefroim'a rod, also insulated for said sleeve extending therethrough and connecting the tip With one of the other terminals, the remaining terminal being insulated from said tip and sleeve and serving solely as means forconnecting together terminals'- of the different devices, the other terminals of the devices being respectively connected to the tip and sleeve members, and

a cap on the side of the disc remote from the tip forming with said disc means for covering and concealing the said three terminals.

3 In a telephone type plug of the classk described, the combination of an insulating material base member, acontact sleeve'extending laterally from said base and having a laterally extending flange engagingsaid base, a Washer on said sleeve against said flange and fastened to said base at a point spaced from said sleeve, a terminal secured to the opposite side of said base and electrically connected t'o said Washerand by said Washei'gto said sleeve, a tip on the end ofsaid sleeve, insulated therefrom and having a conductormember extending through said sleeve, a second terminal secured to said opposite side ofsaid base and electrically connected to said conductor member, a third terminal on said opposite side, insulated fromthe other terminals means for connecting together a pair `of conductors, and a cover removably mounted on. said base for concealing said terminals.

WALTER H; TRIMM.

and provided with; 

